Guaido is a very powerful government figure who disagrees with Maduro and he's claiming that because Maduro didn't win the election fairly the Presidency is up for grabs.
Crucially, he has consistently retained the support of the military high command.
"The time for debate is done".
The United States, Canada and more than a dozen Latin American countries have rallied around Guaido. The leftist leaders of Mexico, Cuba and Bolivia are backing Maduro.
Exactly 61 years before Guaido pledged before swarms of supporters to serve as Venezuela's interim president, the military ousted dictator Marco Perez Jimenez, who fled on a plane to the Dominican Republic amid mounting unrest.
Guaido's bold move came amid a fresh wave of deadly street clashes between protesters and security forces in this oil-rich but economically devastated country. It also advised American citizens in Venezuela - who number nearly 50,000 - to leave while they can. Venezuela owes more than $20 billion.
"It is noteworthy that Venezuela's intelligence services and police are able to cope with large-scale protests, so it is important to make sure that the current situation remains within the framework of the police rather than army operations", he explained.
"The self-declaration of Juan Guaido, as the acting president of Venezuela and immediate recognition of him by USA and other regional states, clearly shows the grand design going on against the legitimately elected President of the Bolivarian Republic of Venezuela, President Nicolas Maduro and Venezuelan People", said NCP Co-chair Pushpa Kamal Dahal in the statement.
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Ant McPartlin and Declan Donnelly , (left) were pictured back to work together for the first time in nearly a year on Friday. After arriving at the back entrance of the theatre in an SUV they greeted fans, but did not answer questions from the media.
On Wednesday, violence flared once again in the South American country and at least 12 people were reported killed in the escalating confrontation with President Nicolas Maduro, who has drawn increasing global criticism.
The department says it's taking the step for security reasons and that the embassy in Caracas will stay open.
The US State Department said that as it no longer recognised Maduro as president, it did not accept his authority to sever ties or declare its diplomats "persona non grata".
Juan Guaido has the support of a lot of the population but even with this support he can't really make Maduro quit. "We commend the contributions of regional governments and all global donors, and encourage additional contributions from the worldwide community to meet growing needs in Venezuela and the region".
UN Secretary General Antonio Guterres, speaking at the World Economic Forum in Davos, appealed for dialogue to keep the crisis from spiralling out of control, warning it could lead "to the kind of conflict that would be a disaster for the people of Venezuela and for the region".
Diplomats at the Organization of American States held an emergency meeting Thursday on the Venezuelan crisis, during which 16 nations recognized Guaido as interim president.
"I warn the Venezuelan people that a coup is being carried out against our democracy's institutionality, against our constitution, against President Nicolas Maduro, the legitimate president", Vladimir Padrino told reporters in the company of other senior military officials.
"Don't trust the gringos", he said, adding they only have "the ambition to take Venezuela's oil, gas and gold".